Help me get to the USA to help others

Hey there! My name is Jack, and I really need your help. I've been given an opportunity to travel to the United States in order to work with children who have life-altering diagnoses. I have worked with this organization in the past, and it was the most meaningful experience of my life. My team and I truly made a positive difference in so many young lives, and that in essence is what I'm asking for help towards. Their mission, our mission, giving kids who have spent a significant portion of their lives in hospital and/or chronic pain a week to just be kids in a place without prejudice or judgement is noble and just. And it is one I genuinely want to dedicate my life to. But I can't do this alone. I'm doing the best I can to get over there, but due to countless factors regarding work available to me here in NZ, I have been unable to save anything meaningful. So I'm here, asking for support. Please help me, because all I want to do is help them.

So if you have anything at all to spare, I would be eternally grateful. In advance, thank you from the bottom of a heart that beats in service of those less able.